1. 9 Lives Body Armor, Inc. produces and extremely unique type of body armor that is patented. 9 Lives is the only company in the world that possesses the technology to manufacture body armor that stops a bullet from literally any type of handgun, shotgun or rifle manufactured today. In addition to local, state, and federal law enforcement units, numerous private sector groups, individuals, and third world country have created a very high demand for this product.

The demand equation is given as   P = 2000 - .4Q
where Q is the annual sales quantity in suits of armor and P is the price per suit.
The firms total cost equation is   C = 900,000 + 250Q

a. To maximize profits, how many suits of armor should 9 Lives produce and sell?

What price should 9 Lives charge?

 
To maximize profits, set MR = MC

TR = P x Q = 2000Q - .4Q

MR = 2000 - .8 Q

MC = 250

2000 - .8Q = 250

Q = 2,187.5….. Q = 2,187

 

P =2000 - .4(2,187) = 2000 - 875 = $1,125

P = $1,125, Q = 2,187

 

  1. Compute the total profit for 9 Lives in this monopoly environment.

 
P = rev - cost = [2000(2187) - .4(2187)­ 2] - [900,000 - 250(2187)]

4374000 - 1913187 - 900000 - 546750

 
Õ = $1,014,062

 
The US Government quickly grows fearful that this type of armor will threaten national security. It immediately limits production of this armor to 1,000 suits per year and implements a serial number registration system so the government can track the users of this equipment.

 

  1. What effect does this have on price and profit for 9 Lives?

P = 2000 - .4(1,000)

P = 1,600 per suit

 

Õ = [2000(1000) - .4(1000)­ 2] - [900000 + 250(1000)]

 

Note that although the regulated production leads to a higher price, profits are reduced because the optimal price is lower. Higher prices do not mean higher profits.
 

  1. Based on the decrease in profits due to government intervention, should the government offer some type of subsidy to 9 Lives to make up the loss?

No. In an ordinary free-market society, one's initial reaction may be to say that

the Government should reimburse this company for the loss in profits. Due to the

nature of the business, however, it is in the publics best interest for the

Government to regulate this type of product. There are many illegal products

that would be extremely profitable in today’s economy if they were allowed to be

sold on the free market, but those products are illegal for a reason and that is for

the benefit of the general public and the welfare of the nation. While this product

was not declared "illegal", it was recognized to pose a significant risk to the

ability of our law enforcement/military personnel to control the actions of

potentially dangerous people that might use this product to enable them to

conduct illegal activities without the fear of deadly force being used to stop them.

 

Note: In addition to regulation, the government must impose some enforcement mechanism. 9 lives would like like to expand production and lower prices, and there are willing buyers. There is thus the possibility of "black markets" and illicit production.

 

2. McMurphy is one of a handful of OU students that are currently manufacturing and selling home brew beer on campus. McMurphy's business is in a monopolistcally competitive market and his weekly demand and cost functions are as follows:
 

P=10-.25Q and C=50+.5Q

 
a. What are McMurphy's optimum short term price, quantity and profits?

 
MR=10-.5Q MC=.5

10-.5Q=.5

Q=19 and P=5.25

P =TR-C=99.75-59.5=40.25
 

b. It seems likely that other students will also find it profitable to make their home brews for sale. What should McMurphy expect his long term equilibrium price and quantity to be?

 
AC=(50+.5Q)/Q

 
dp/dq=dac/dq (The demand must be tangent to AC as a result of entry)

 
-.25=-50/Q2

Q=14

AC=P

P=(50+.5(14))/14=4.07

 
c. Can this market becomes perfectly competitive? If so, determine the long-run equilibrium price and quantity.

In perfect competition, price must go to the minimum of the AC. With a U-shaped cost curve, find the minimum by in the usual way taking the derivative of AC. Here, however, the AC is not U-shaped; MC is constant at 0.5. Thus the market is incompatible with a firm being a price-taker (i.e., both the MC and MR would be horizontal).

 

3. It is the year 2050 and the market for lunar travel (spaceship from earth to the moon) is extremely regulated. The barriers to entry of new spaceship companies are enormous, and flight fares are set by regulation. Suppose that the annual lunar travel demand is estimated to be Q=300000-5P(or P=60000-Q/5), where Q is the number of trips in thousands and P is theone-way fare in dollars. (For example, 250000 annual trips are taken when the fare is $10,000). Also, the long-run average (one way) cost per passenger is estimated to be $6000.

A distinguished (and by now very old) economist named Prof. Santo believes that there is an implicit cartel among lunar travel providers whereby they are charging monopoly fares under the disguise of regulation!

 

a. Knowing these facts, what is the annual number of passenger trips?

 

A profit maximizing cartel sets the MR=MC. Thus, 60000-2Q/5=6000

therefore, Qm=135000

 

b. Find the profit-maximizing fare.

 

Pm=60000-135000/5=$33000

 

Suppose that lunar travel became deregulated so that flights to the moon

became perfectly competitive.

 

c. Find the competitive price.

 

Under perfect competition, Pc=LAC=$6000

d. What is the competitive quantity?

 

Qc=300000-(5)(6000)=270000

 

e. What kind of barriers helps protect the lunar travel cartels monopoly

position?

 

The overwhelming barrier to entry is the enourmous capital requirements

involved in the production and maintenaince of building high quality

spaceships. Although this is the greatest barrier, there are others such

as patents, legal barriers, and the control of resources (such as diamond

tipped landing gear) to name a few.

 

 4. CAF Corporation and AM Corporation comprise a cartel that controls the diamond market.

CAF Corporation has a marginal cost of MCCAF = 24 + 6QCAF

AM Corporation has a marginal cost of MCAM = 10 + 2QAM

After a recent meeting the firms decided to maximize the total profit for their cartel. Most recent surveys have show that market demand for diamonds is P = 250-Q. Q is the total output of the cartel.

  1. The optimal price and optimal output for the cartel are?
  2. The cartel decides after some time to produce only 20 units. What output should each firm produce to minimize total cost?
  3. What is each firm’s marginal cost when the cartel produces 20 units?
  4. CAF Corporation comes to AM Corporation and says it is going to expand its output to 30 units to increase its profits. How will CAF Corporation’s increasing it’s output effect the cartel?

Answers

a. MR = MCCAF = MCAM

250 - 2Q = 24 + 6QCAF = 10 + 2QAM

250 - 2(QCAF + QAM) = 24 + 6QCAF = 10 + 2QAM

QCAF = QAM

250 - 4Q = 24 -6Q = 10 + 2Q

Q = 27

P = 223

 

b. 24 + 6QCAF = 10 + 2QAM

QCAF + QAM = 20

7 + 3QCAF = 20 - QCAF

QCAF = 13/4 = 3

QAM = 67/4 = 17

 

c. MCCAF = 24 + 6QCAF = 24 + 6*3 = 42

MCAM = 10 + 2QAM = 10 + 2*17 = 44

 

d. MR at Q = 20 is 250 - 2Q = 210

This MR of 210 exceeds the MC of both firms so by expanding production to 30 units CAF Corporation can increase its profits. In the long run however this strategy will not work. AM Corporation will want to increase its output it match the profits of CAF Corporation and this competition will damage the cartel and ultimately destroy the cartel.

 

5. The Starhopper Corporation has created the first and only transportation vehicle designed for interplanetary space travel with a revolutionary, low cost, power source. The demand function is as follows:

Q = f (P, E, S, A, PS, C)

Where P = price per vehicle

E = economy

S = current safety concerns of space travel

A = asteroid projections (current news)

PS = availability of power supply

C = claustrophobia/gravity rating (% of persons able to withstand

Space travels limitations)

Due to current news reports on near asteroid collisions the demand equation is large and has the following formula:

QD = 456008 - 0.35P + 4.76E + 75.86S + 2456A + 57.6PS + 36.7C

a. For the last four months, the Starhopper Corporation has been selling their StarM5 vehicle. They are a monopoly and have acquired the patents necessary to remain so for the near future. The current economy is good at 5.2, current safety concerns are wavering at 74, the current news has been talking of nothing else the last few weeks (67 pts), most persons are able to withstand space travel (89%) and the power supply is projected to last for the next millenium (1000 years). The short run cost per vehicle is as follows:

STC = 3455400 + 250Q + 764.3Q2

In order to maximize their profit, how many StarM5's should they plan to produce? At what price? What will be the profit?

MC = dTC = 250 + 1528.6

dQ

QD = 456008 - 0.35P + 4.76 (5.2) + 75.86 (74) + 2456 (67) + 57.6 (1000) + 36.7 (0.89)

QD = 683,831.055 - .0.35P Þ P = 1,953,803 - 2.857Q

 

R = P x Q = 1,953,803Q - 2.857Q2

 

MR = dR = 1,953,803 - 5.714Q

dQ

 

To maximize monopoly profit set MR = MC

 

2500 + 1528.6Q = 1,953,803 - 5.714Q

Q = 1273.24 Þ 1273

P = $1,950,166

p = R - C = 2,482,561,318 - 1,242,343,965 = $1,240,217,353

 

b. Because of the revolutionary new power source that Starhopper has created using Methane gas, it now falls within the category of a natural monopoly and the long run average cost is declining to the following equation:

LAC = 1714.52 - 0.568 - 0.45892Q

Q

What is the new quantity, price and profit?

 

To maximize natural monopoly profit set MR = MC

MR = 1,953,803 - 5.714Q

LTC = LAC x Q = 1714.52 - 0.568Q - 0.45892Q2

LAMC = dLTC = - 0.568 - 0.91784Q

dQ

1,953,803 - 5.71Q = - 0.568 - .61784Q

Q = 383688.566 Þ 383688

P = $857,606

p = R - C = (P x Q) - C = 3.2905313 x 1011 - (-6.7560803 x 1010 ) = 3.9661393 x 1011

Þ $396,613,930,000

 

c. The government decides to regulate this industry and initiates average-cost pricing. Under this new policy what is the new quantity and price?

Set P = AC

1,953,803 - 2.857Q = 1714.52 - 0.568 - 0.45892Q

Q

______

Using the quadratic equation: - b ± Ö b2 - 4ac

2a

 

________________________________

Q = - 1,953,803.568 ± Ö 1,953,803.5682 - 4 (-2.39808) (1714.52)

2(-2.39808)

Q = -0.000877785, 448,105.8055

As it cannot be negative, Q = 448,105

P = $673,564.71

d. Scientists at Starhopper are worried that NASA will decide that it can also get in on the profits and chooses to enter into competition. As NASA would have to develop a different power source (due to patents) their costs would be a bit higher but their reputation should earn them close to the following demand and cost equations:

QNASA = 6890210 - 0.35P + 4.76E + 75.86S + 2456A + 265PS + 36.7C

TCNASA = 5867271 +583Q +749.254Q2

All factors should stay the same except that their probable power supply is expected to last only 150 years, therefore: QNASA = 898,994 - 0.35P PNASA = 2,568,554 - 2.857Q

Is NASA a potential threat? What are its expected quantities and price?

MC = dTC = 583 + 1498.508Q

dQ

QD = 890210 - 0.35P + 4.76 (5.2) + 75.86 (74) + 2456 (67) + 265 (150) + 36.7 (0.89)

QD = 1,100,183 - .0.35P Þ P = 3,143,380.157- 2.857Q

 

R = P x Q = 3,143,380.157Q - 2.857Q2

 

MR = dR = 3,143,380.157 - 5.714Q

dQ

 

To maximize profit set MR = MC

 

583 + 1498.508Q = 3,143,380.157 - 5.714Q

Q = 2089.317 Þ 2089

P = $3,137,411.88

This would definitely pose a threat to future profits!

e. Assuming a perfectly competitive situation, the industry demand and supply curves are expected to be the following:

Q = 449,497 - 0.35P S = MC = 333 + 756.8Q

What would the new price be for both companies in a perfectly competitive market?

Under perfect competition P = MC

1,284,277.143 - 2.857Q = 333 + 756.8Q

QI = 1690

PI = $1,279,325.00

f. Determined not to get caught in this situation and hearing rumors that NASA is contemplating entering the industry, Starhopper proposes forming a cartel with NASA. Will NASA agree?

No, cartels are illegal within the United States, unless the government allows a special exemption under the antitrust laws. It would probably include strict pricing, profit and quantity restrictions As NASA is a governmental department this might occur depending on the need for space travelling vehicles.

g. In the event that a cartel can not be formed, what other options is open to Starhopper to dissuade competition?

The following barriers to entry are common:

 

6. Tortilla Bell is a new restaurant. Based on the fact that it has a unique menu and waitresses with special uniforms, the restaurant commands a premium price. In the short run, the demand curve and cost equations for a Premium Tortilla Plate per day are:

P = 8 - .025Q C = 100 + 4Q

a. What are the short term, profit-maximizing output, price, and profit?

MC = dC/dQ = 4 TR = 8Q - .025 Q2 MR = dTR/dQ = 8 - .050 Q

MR = MC 8 - .050 Q = 4 Q = 80 P = 8 - .025 (80) = $6.00

p = TR -TC = [ 8 (80) - .025 (80)2] - [ 100 + 4 (80)] = 480 - 420 = $ 60

 

b. Determine the long run price and output assuming that the demand curve shifts in a parallel manner.

Slope of demand = slope of AC AC = (100 + 4Q)/Q = 100/Q + 4

dP(demand)/dQ = dP(AC)/dQ d(8 - .025Q)/dQ = d(100/Q + 4)/dQ

-.025 = -100/Q2 Q2 = 4000 Q = 63

P = AC = 100/63 + 4 = $ 5.58

 

c. What can Tortilla Bell do to again start making economic profits?

 

Tortilla Bell needs to do something to differentiate its product again - for example, by introducing a new special menu or by introducing new services. The pressure on firms to innovate and thereby provide consumers with choices illustrates one of the major benefits of monopolistically competitive markets.

 

 

7. A bright young entrepreneur has opened an exclusive new fly-in restaurant at a local airport called Barnstormers!. Barnstormers! cater to business and general aviation customers with services such as ordering ahead by radio, "fly away" orders, and of course, the convenience of aircraft parking on the premises! Because of the niche nature of their business, Barnstormers! has no direct competition, although there are several restaurants within a short taxi ride of the airport. Barnstormers! total cost and demand equations are as follows:

Total Cost = 2300 + 2.25Q Total Demand = 2020 – 98P.

 

  1. What are Barnstormers! profit maximizing output, price, and profit?
  2.  

  3. Because of the economic profits that Barnstormers! has enjoyed, two competing restaurants which are close to the airport attempt to service the same customers by providing limousine service to their restaurants and order delivery to the airport. With new competition, Barnstormers! demand changes to Qd = 1678 – 105P. What is the change in Barnstormers! output, price, and profit?
  4.  

  5. Being a fierce competitor, Barnstormers! uses its vast cash reserves to launch a regional ad campaign to increase demand, while reducing its prices by 50% in an effort to drive out the competition. As a monopolist, what would be Barnstormers! optimal price and output?
  6.  

  7. If Barnstormers! was unsuccessful in driving out its competitors, what would be eventual outcome of the restaurant market in the area? (Assume that the market demand is Qmd = 1090 – 111P). Draw a sketch showing this outcome.

 

 

Solutions

 

  1. Q = 2020 – 98P Demand equation
  2. P = 20.61 - .0102Q Inverse Demand Equation

    TR = (20.61 - .0102Q)Q

    TR = 20.61Q - .0102Q2 Total Revenue Equation

    MR = 20.61 - .0204Q Marginal Revenue Equation

    TC = 2300 + 2.25Q Total Cost Equation

    MC = 2.25 Marginal Cost

     

    MR = MC 900 = 2020 – 98P

    20.61 - .0204Q = 2.25 98P = 1120

    18.36 = .0204Q P = $ 11.43

    Q = 900

     

    TP = TR – TC

    = (900 x 11.43) – [2300 + (2.25 x 900)]

    TP = $ 5962

     

     

  3. Q = 1678 - 105P Demand equation
  4. P = 15.98 - .0095Q Inverse Demand Equation

    TR = (15.98 - .0095Q)Q

    TR = 15.98Q- .0095Q2 Total Revenue Equation

    MR = 15.98- .019Q Marginal Revenue Equation

    TC = 2300 + 2.25Q Total Cost Equation

    MC = 2.25 Marginal Cost

     

    MR = MC 722 = 1678 – 105P

    15.98- .019Q = 2.25 105P = 956

    13.73 = .019Q P = $ 9.10

    Q = 722

     

    TP = TR – TC Quantity decreased by 178

    = (722 x 9.10) – [2300 + (2.25 x 722)] Price decreased by $2.24

    TP = $ 2645.70 Total Profits decreased by $3316.30

     

     

     

  5. Assuming that Barnstormers!’ demand is the market demand, the restaurant simply sets MR = MC to derive its optimal price and output.
  6.  

     

  7. We need dP/dQ=dAC/dQ assuming a parallel shift in demand until it is tangent to the AC.

Q = 1090 – 111P

P = 9.82 - .009Q

dP/dQ=-0.009

 

With AC=2300/Q + 2.25, dAC/dq=-2300/Q2

 

Solving: Q2=255556 and Q=506

 

Thus P=AC=6.80

 

 

The market equilibrium quantity is 506 and price is $6.80. At this level, the firm has no economic profit.